Locally-actuated partial stroke testing system

ABSTRACT

Embodiments of the present disclosure describe both mechanically-operated and electrically-operated, locally-actuated partial stroke testing devices and systems for testing operation of an emergency isolation valve.

FIELD

The disclosure relates to a locally-actuated partial stroke testingsystem for testing operation of emergency isolation valves.

BACKGROUND

Partial stroke testing (PST) is a method used in a process controlsystem to allow testing of a selected percentage of possible failuremodes of an emergency isolation valve (EIV) without completelyphysically closing the valve. Generally, PST is performed via a computercontrol system where the system communicates with an EIV to partiallyclose the valve and then open the valve. The purpose of PST is todetermine whether an EIV is operating properly to ensure safe operationof an industrial process in the event that an emergency requires closingof the EIV. PST is common in the oil, gas, petrochemical, and powerindustries, and numerous computer based control systems with PSTcapability.

Generally, computer based PST systems are operated remotely and haverelatively complicated designs, including complex wiring, multipleinput/output lines, voluminous documentation, full stroke/complexcalibration, and numerous design components such as boosters.Furthermore, some computer based PST systems may be sensitive to airquality, and online replacement may not be an option due to requirementsof full stroke for accurate positioner calibration. Moreover, somesystems may have continuous air consumption and power consumption duringoperation and further may have additional height requirements to a valvethus requiring more space for installation.

SUMMARY

Certain specific embodiments of this disclosure have been described ingreat detail here. In an effort to provide a concise description ofthese embodiments, all features of an actual implementation may not bedescribed in the specification. In the development of any such actualimplementation, as in any engineering or design project, numerousimplementation-specific changes may be made to achieve specific goals,such as compliance with system-related and business-related constraints,which may vary from one implementation to another. Such a developmenteffort might be complex and time consuming, but nevertheless it would bea routine undertaking of design, fabrication, and manufacture for thoseof ordinary skill having the benefit of this disclosure.

Certain embodiments include a locally-actuated partial stroke testingdevice for testing a single acting emergency isolation valve. The deviceincludes a mechanically-operated valve; a flow control valve coupled toa vent port of the mechanically-operated valve, the flow control valvebeing operable to regulate air flow from the vent port; and a valveposition indicator to convey position of the single acting emergencyisolation valve, the valve position indicator being in visual proximityto the mechanically-operated valve.

The flow control valve can be integrated to the vent port of themechanically-operated valve. The mechanically-operated valve can be a3/2 manually-operated valve. The mechanically-operated valve can be a5/2 manually-operated valve. Certain embodiments may further include anair supply line coupled to an input port of the mechanically-operatedvalve, the air supply line having an air filter regulator to filter andregulate air supplied to the input port; a 3/2 solenoid valve with afirst port coupled via an air flow line to a working port of themechanically-operated valve; and a working flow line coupled between asecond port of the 3/2 solenoid valve and a port of the single actingemergency isolation valve, the working flow line to providebidirectional air flow.

Certain embodiments include a locally-actuated partial stroke testingdevice for testing a double acting emergency isolation valve. The deviceincludes a mechanically-operated valve with a first vent port, a secondvent port, a first working port, and a second working port, wherein thefirst and second vent ports are operable to vent air from themechanically-operated valve, and the first working port is coupled to afirst flow control valve and the second working port is operable toregulate the air flow to a first solenoid valve coupled to the doubleacting emergency isolation valve. This device also includes the firstflow control valve operable to regulate the air flow to a secondsolenoid valve coupled to the double acting emergency isolation valve;and a second flow control valve coupled to the first vent port of themechanically-operated valve, the second flow control valve beingoperable to regulate air flow; and a valve position indicator to conveyposition of the double acting emergency isolation valve, the valveposition indicator being in visual proximity to themechanically-operated valve. The mechanically-operated valve can be a3/2 manually-operated valve. The mechanically-operated valve can be a5/2 manually-operated valve. The first flow control valve can beintegrated with the first working port of the mechanically-operatedvalve. The second flow control valve can be integrated with the firstvent port of the mechanically-operated valve.

Certain embodiments include an electrically-operated, locally-actuatedpartial stroke testing device for testing a single acting emergencyisolation valve. The device includes a 3/2 solenoid valve coupled to anelectrical actuator; a flow control valve coupled to a vent port of the3/2 solenoid valve, the flow control valve being operable to regulateair flow; and a valve position indicator to convey position of thesingle acting emergency isolation valve, the valve position indicatorbeing in visual proximity to the 3/2 solenoid valve.

Certain embodiments of the device further include an air supply linecoupled to an input port of the 3/2 solenoid valve, the air supply lineincluding an air filter regulator to filter and regulate air supplied tothe input port; a second 3/2 solenoid valve with a first port coupledvia an air flow line to a working port of the first 3/2 solenoid valve,the second 3/2 solenoid valve being a universal type 3/2 solenoid valvewith an exhaust port; and a working flow line coupled between a secondport of the second 3/2 solenoid valve and a port of a single actingemergency isolation valve, the working flow line to providebidirectional air flow. In certain embodiments, the flow control valveis integrated with the vent port of the 3/2 solenoid valve. Theelectrical actuator can include a partial stroke testing limit switchingcircuit.

Certain embodiments include a locally-actuated partial stroke testingdevice for testing a double acting emergency isolation valve. The deviceincludes a first solenoid valve with an electrical actuator, a firstvent port, a second vent port, a first working port, and a secondworking port, wherein the first and second vent ports is operable tovent air from the first solenoid valve, and the first working port iscoupled to a first flow control valve and the second working port isoperable to regulate the air flow to a second solenoid valve coupled tothe double acting emergency isolation valve. The device further includesthe first flow control valve operable to regulate the air flow to athird solenoid valve coupled to the double acting emergency isolationvalve; a second flow control valve coupled to the first vent port of thefirst solenoid valve, the second flow control valve being operable toregulate air flow; a valve position indicator to convey position of thedouble acting emergency isolation valve, the valve position indicatorbeing in visual proximity to the first solenoid valve. The first flowcontrol valve can be integrated with the first working port of the firstsolenoid valve. The second flow control valve can be integrated with thefirst vent port of the first solenoid valve. In certain embodiments, thedevice further includes a partial stroke testing limit switchingcircuit. The valve position indicator can convey a percentage ofdiameter of the double acting emergency isolation valve open to fluidflow. The valve position indicator can utilize one or more of color,numerical, alphabetical, or graphical marks or combinations thereof toconvey the percentage of diameter of the double acting emergencyisolation valve open to fluid flow.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by a person having ordinary skillin the art by reading the detailed description in conjunction with theaccompanying drawings. To facilitate the description, like referencenumerals designate like structural elements or procedures in a method.Embodiments may be illustrated by way of examples and drawings.

FIG. 1 schematically illustrates a mechanically-operated,locally-actuated partial stroke testing device for testing a singleacting emergency isolation valve, in accordance with variousembodiments.

FIG. 2 schematically illustrates a mechanically-operated,locally-actuated partial stroke testing device for testing a doubleacting emergency isolation valves, in accordance with variousembodiments.

FIG. 3 schematically illustrates an electrically-operated,locally-actuated partial stroke testing device for testing a singleacting emergency isolation valve, in accordance with variousembodiments.

FIG. 4 schematically illustrates an electrically-operated,locally-actuated partial stroke testing device for testing a doubleacting emergency isolation valve, in accordance with variousembodiments.

DETAILED DESCRIPTION

The present disclosure describes various embodiments related tolocally-actuated partial stroke testing systems for testing operation ofemergency shutdown valves. Further embodiments may be described anddisclosed.

In the following description, numerous details are set forth in order toprovide a thorough understanding of the various embodiments. In otherinstances, well-known processes, devices, and systems may not beendescribed in particular detail in order not to unnecessarily obscure thevarious embodiments. Additionally, illustrations of the variousembodiments may omit certain features or details in order to not obscurethe various embodiments.

In the following detailed description, reference is made to theaccompanying drawings that form a part of this disclosure. Like numeralsmay designate like parts throughout the drawings. The drawings mayprovide an illustration of some of the various embodiments in which thesubject matter of the present disclosure may be practiced. Otherembodiments may be utilized, and logical changes may be made withoutdeparting from the scope of this disclosure.

The description may use the phrases “in some embodiments,” “in variousembodiments,” “in an embodiment,” or “in embodiments,” which may eachrefer to one or more of the same or different embodiments. Furthermore,the terms “comprising,” “including,” “having,” and the like, as usedwith respect to embodiments of the present disclosure, are synonymous.

Various embodiments of locally-actuated partial stroke testing (PST)devices and methods are disclosed and described. The various embodimentsprovide devices and methods that are intrinsically safe, simple indesign and operation, and economic, in comparison to various commercialPST devices and systems. The PST may be locally-actuated (LAPST) and maybe used for testing single acting or double acting emergency isolationvalves. The PST may be locally-actuated by mechanical-based methods orelectrical-based methods. In the mechanically-based PST method andsystem, a mechanically operated valve may be used in the PST method.Some of the mechanical-based devices and methods may involve manualoperation of a mechanical valve to perform PST. The valve may includeany type of mechanical device to operate the valve. The valve is todivert air to and from the actuator. The system may further include aunidirectional flow control valve for a single acting actuator. Thevalve may be a 3/2 type for a single acting actuator. The system mayfurther include two unidirectional flow control valves for double actingactuators. The valve may be a 5/2 type for a double acting actuator. Theunidirectional flow control valve may provide full bore flow in onedirection and a restricted flow in the opposite direction. Theunidirectional flow control valve is to slow down the rate ofpressurizing and venting of air from the actuator in the direction ofthe restricted flow (away from the valve). Isolation and bypass valvesmay be included in the PST system to provide a mechanism for onlinereplacement and isolation of the PST system, and a limit switch at theintended stroke test position may be included in the PST system to set aselected percentage to provide an alarm. Some of the various embodimentsmay be electrical-based devices with push button operation of a solenoidvalve to perform PST. The various embodiments do not need an interfacewith an emergency shutdown system (logic solver) as they arelocally-actuated near the valve being tested. The various embodimentsmay be used for fail-open, fail-close, single acting, and double actingactuators. The various embodiments include locally actuating a partialstroke testing by pressing a button or moving a lever or key whilevisually monitoring the valve movement via a local valve positionindicator on the valve being tested. In various embodiments, a partialstroke testing will finish when the target position of the valve isreached, at which point the testing button/lever/key is released toallow the valve to return to its original position prior to initiationof PST. In various embodiments, the display device and the valveposition indicator are in visual proximity to the locally-actuatedpartial stroke testing device. In various embodiments, a display devicemay be mounted on a panel next to the valve to ease viewing the localvalve position indicator during the testing. The display devices caninclude indicators that show the “open” or “close” positions of thevalve along with the percentage of “open” or “close” position of thevalve. These indicators can include color, numerical, alphabetical, orgraphical marks or combinations of these marks to show the valveposition. In certain embodiments, the valve position indicator conveys apercentage of diameter of the double acting emergency isolation valveopen to fluid flow. In certain embodiments, the valve position indicatorutilizes one or more of color, numerical, alphabetical, or graphicalmarks or combinations thereof to convey the percentage of diameter ofthe double acting emergency isolation valve open to fluid flow.

FIG. 1 schematically illustrates a mechanically-operated,locally-actuated partial stroke testing device 100 for testing a singleacting emergency isolation valve 102, in accordance with variousembodiments. The device 100 includes a mechanically-operated valve 104.The mechanically-operated valve 104 can be a 3/2 or 5/2 hand operatedvalve. The device 100 further includes a flow control valve 106 coupledto a vent port 108 of the mechanically-operated valve 104. An air supplyline 110 is used to provide air to an input port 112 of themechanically-operated valve 104. The air supply line 110 can incorporatean air filter regulator 114 to filter and regulate air supplied to theinput port 112. The device 100 includes a mechanical device 105 such asa push button or lever or key to operate the mechanically-operated valve104. The device 100 is locally-actuated via device 105 in contrast toremotely actuated via a computer logic controller system. A displaydevice may be mounted on a panel next to the emergency isolation valve102 for easy viewing of the valve position indicator during the testing.The device 100 further is coupled via an air flow line 120 to a 3/2solenoid valve 116, such as a SIL 3 solenoid valve, with a first port118. The air flow line 120 connects a working port 122 of the handoperated valve 104 to the first port 118 of the solenoid valve 116. Inthis embodiment, the working flow line 124 establishes a connectionbetween a second port 126 of the solenoid valve 116 and a port 128 of asingle acting emergency isolation valve 102. The working flow line 124provides bidirectional air flow. The flow control valve 106 restrictsair flow from the vent port 108 of the hand operated valve 104 in adirection 109 away from the valve 104. In this embodiment, the 3/2solenoid valve 116 is a universal type normally energized 3/2 solenoidvalve. In other embodiments, the flow control valve 106 may beintegrated within the vent port 108 of the valve 104. The valve 104 maybe manufactured with the flow control valve 106 as a design element ofthe valve 104 to provide an integrated valve with a flow controller. Invarious embodiments, the 3/2 solenoid valve 116 further contains anexhaust port 130. Flow through the 3/2 solenoid valve 116 isbidirectional, with the direction depending on progression of a PST ofvalve 102.

FIG. 2 schematically illustrates a mechanically-operated,locally-actuated partial stroke testing device 200 for testing a doubleacting emergency isolation valve 202, in accordance with variousembodiments. The device 200 includes a 5/2 mechanically-operated valve204 with a first vent port 208 and a second vent port 213, where thefirst vent port 208 and second vent port 213 are used to vent air fromthe 5/2 mechanically-operated valve 204 to shut-off valves. The device200 further includes a first flow control valve 206 coupled to the firstvent port 208 of the 5/2 mechanically-operated valve 204. The flowcontrol valve 206 is used to restrict or allow air flow from the firstvent port 208. An air supply line 210 is used to provide air to an inputport 212 of the 5/2 mechanically-operated valve 204. The air supply line210 can include an air filter regulator 214 to filter and regulate air.A first 3/2 solenoid valve 216 with a first port 218 is coupled via afirst working line 220 to a first working port 222 of the 5/2mechanically-operated valve 204. The first 3/2 solenoid valve 216 can bea universal type normally energized 3/2 solenoid valve and includes anair inlet port 229. The first working port 222 is operably coupleable tothe second vent port 213 via positioning of a mechanical device 205 ofthe 5/2 mechanically-operated valve 204. The mechanical device 205 maybe a lever or push button or key or some other type of mechanical devicefor operation of the 5/2 mechanically-operated valve 204. The device 200can include a second flow control valve 207 operating on the firstworking line 220 between the first working port 222 of the 5/2mechanically-operated valve 204 and the first port 218 of the first 3/2solenoid valve 216. The second flow control valve 207 is used torestrict or allow air from first working port 222. A second working flowline 224 connects a second port 226 of the first 3/2 solenoid valve 216with a first port 228 of a double acting emergency isolation valve 202.A second 3/2 solenoid valve 217 with a first port 240 is coupled to thedevice 200 via a third working line 242 to a second working port 244 ofthe 5/2 mechanically-operated valve 204. In certain embodiments, thesecond 3/2 solenoid valve 217 is a universal type normally energized 3/2solenoid valve and includes an exhaust port 230. The second working port244 is operably coupleable to the first vent port 208 of the 5/2mechanically-operated valve via positioning of a mechanical device 205.A fourth working flow line 234 connects a second port 236 of the second3/2 solenoid valve 217 and a second port 238 of the double actingemergency isolation valve 202. The device 200 can further include thefirst flow control valve 206 integrated with the first vent port 208 ofthe 5/2 mechanically-operated valve 204. The valve 204 may bemanufactured with the flow control valve 206 as a design element of thevalve 204 to provide an integrated valve with a flow controller. Thedevice 200 can further include the second flow control valve 207integrated with the first working port 222 of the 5/2mechanically-operated valve 204.

FIG. 3 schematically illustrates an electrically-operated,locally-actuated partial stroke testing device 300 for testing a singleacting emergency isolation valve 302, in accordance with variousembodiments. The device 300 includes a 3/2 solenoid valve 304 includingan electrical actuator 305, where the valve is normally de-energizedduring periods in which the device 300 is not being used for PST ofvalve 302. The electrical actuator 305 may be a push button for exampleor some other type of actuator to provide an electrical signal toinitiate a PST of valve 302. The device 300 can include a flow controlvalve 306 coupled to a vent port 308 of the 3/2 solenoid valve 304. Theflow control valve 306 is used to restrict or allow air flow from thevent port 308. An air supply line 310 is used to provide air to an inputport 312 of the 3/2 solenoid valve 304. The air supply line 310 canincorporate an air filter regulator 314 to filter and regulate airsupplied to the input port 312. A second 3/2 solenoid valve 316 with afirst port 318 is coupled via an air flow line 320 to a working port 322of the 3/2 solenoid valve 304. In certain embodiments, the second 3/2solenoid valve 316 is a universal type normally energized 3/2 solenoidvalve with an exhaust port 330. The second 3/2 solenoid valve 316 isnormally energized during periods in which the valve 302 is notundergoing PST. The device 300 can further include a working flow line324 coupled between a second port 326 of the second 3/2 solenoid valve316 and a port 328 of the single acting emergency isolation valve 302,where the working flow line 324 operates to provide bidirectional airflow. In certain embodiments, the device 300 can further include theflow control valve 306 integrated with the vent port of the 3/2 solenoidvalve 304. The device 300 can further include an electrical actuator 305and a PST limit switching circuit. This limit switch acts as an extraprotective measure to indicate whether the valve 302 has moved to aparticular location associated with successful partial stroke testing,such as the valve 302 being at a 80% or 90% open position.

FIG. 4 schematically illustrates an electrically-operated,locally-actuated electrical partial stroke testing device 400 fortesting a double acting emergency isolation valve 402, in accordancewith various embodiments. The device 400 may include a 5/2 solenoidvalve 404 having an electrical actuator 405 and a first vent port 408and a second vent port 413. The first vent port 408 and second vent port413 are provided to vent air from the 5/2 solenoid valve 404 and thevalve is normally de-energized during periods when the valve 402 is notundergoing PST. The electrical actuator may be a push button for exampleor some other type of actuator to provide an electrical signal toinitiate a PST of valve 402. The device 400 further includes a firstflow control valve 406 coupled to the first vent port 408 of the 5/2solenoid valve 404. The flow control valve 406 is used to restrict orallow air from the first vent port 408. The device 400 further includesa first flow control valve 406 coupled to the first vent port 408 of the5/2 solenoid valve 404. The flow control valve 406 is used to restrictor allow air flow from the first vent port 408. An air supply line 410is used to provide air to an input port 412 of the 5/2 solenoid valve404. The air supply line 410 can include an air filter regulator 414 tofilter and regulate air. A first 3/2 solenoid valve 416 with a firstport 418 is coupled via a first working line 420 to a first working port422 of the 5/2 solenoid valve 404. The first 3/2 solenoid valve 416 canbe a universal type normally energized 3/2 solenoid valve and includesan air inlet port 429. The first working port 422 is operably coupleableto the second vent port 413 via positioning of an electrical actuator405 of the 5/2 solenoid valve 404. The electrical actuator 405 may be abutton or a switch or some other type of electrical device for operationof the 5/2 solenoid valve 404. The device 400 can include a second flowcontrol valve 407 operating on the first working line 420 between thefirst working port 422 of the 5/2 solenoid valve 404 and the first port418 of the first 3/2 solenoid valve 416. The second flow control valve407 is used to restrict or allow air from first working port 422. Asecond working flow line 424 connects a second port 426 of the first 3/2solenoid valve 416 with a first port 428 of a double acting emergencyisolation valve 402. A second 3/2 solenoid valve 417 with a first port440 is coupled to the device 400 via a third working line 442 to asecond working port 444 of the 5/2 solenoid valve 404. In certainembodiments, the second 3/2 solenoid valve 417 is a universal typenormally energized 3/2 solenoid valve and includes an exhaust port 430.The second working port 444 is operably coupleable to the first ventport 408 of the 5/2 solenoid valve via positioning of an electricalactuator 405. A fourth working flow line 434 connects a second port 436of the second 3/2 solenoid valve 417 and a second port 438 of the doubleacting emergency isolation valve 402. The device 400 can further includethe first flow control valve 406 integrated with the first vent port 408of the 5/2 solenoid valve 404. The valve 404 may be manufactured withthe flow control valve 406 as a design element of the valve 404 toprovide an integrated valve with a flow controller. The device 400 canfurther include the second flow control valve 407 integrated with thefirst working port 422 of the 5/2 solenoid valve 404. The device 400further may include a partial stroke testing limit switching circuit.

The various embodiments of the inventions, as set forth infra, areintended to be illustrative, and not limiting. As a result, it will beapparent for those skilled in the art that the illustrative embodimentsdescribed are only examples and that various modifications can be madewithin the scope of the invention as defined in the appended claims.

What is claimed is:
 1. A locally-actuated partial stroke testing devicefor testing a single acting emergency isolation valve, comprising: amechanically-operated valve; a flow control valve coupled to a vent portof the mechanically-operated valve, the flow control valve beingoperable to regulate air flow from the vent port; and a valve positionindicator to convey position of the single acting emergency isolationvalve, the valve position indicator being in visual proximity to themechanically-operated valve.
 2. The device of claim 1, wherein the flowcontrol valve is integrated to the vent port of themechanically-operated valve.
 3. The device of claim 1, wherein themechanically-operated valve is a 3/2 manually-operated valve.
 4. Thedevice of claim 1, wherein the mechanically-operated valve is a 5/2manually-operated valve.
 5. The device of claim 1, further comprising:an air supply line coupled to an input port of the mechanically-operatedvalve, the air supply line having an air filter regulator to filter andregulate air supplied to the input port; a 3/2 solenoid valve with afirst port coupled via an air flow line to a working port of themechanically-operated valve; and a working flow line coupled between asecond port of the 3/2 solenoid valve and a port of the single actingemergency isolation valve, the working flow line to providebidirectional air flow.
 6. A locally-actuated partial stroke testingdevice for testing a double acting emergency isolation valve,comprising: a mechanically-operated valve with a first vent port, asecond vent port, a first working port, and a second working port, thefirst and second vent ports being operable to vent air from themechanically-operated valve, and the first working port being coupled toa first flow control valve and the second working port being operable toregulate the air flow to a first solenoid valve coupled to the doubleacting emergency isolation valve; the first flow control valve operableto regulate the air flow to a second solenoid valve coupled to thedouble acting emergency isolation valve; and a second flow control valvecoupled to the first vent port of the mechanically-operated valve, thesecond flow control valve being operable to regulate air flow; a valveposition indicator to convey position of the double acting emergencyisolation valve, the valve position indicator being in visual proximityto the mechanically-operated valve.
 7. The device of claim 6, whereinthe mechanically-operated valve is a 3/2 manually-operated valve.
 8. Thedevice of claim 6, wherein the mechanically-operated valve is a 5/2manually-operated valve.
 9. The device of claim 6, wherein the firstflow control valve is integrated with the first working port of themechanically-operated valve.
 10. The device of claim 6, wherein thesecond flow control valve is integrated with the first vent port of themechanically-operated valve.
 11. An electrically-operated,locally-actuated partial stroke testing device for testing a singleacting emergency isolation valve, comprising: a 3/2 solenoid valvecoupled to an electrical actuator; a flow control valve coupled to avent port of the 3/2 solenoid valve, the flow control valve beingoperable to regulate air flow; and a valve position indicator to conveyposition of the single acting emergency isolation valve, the valveposition indicator being in visual proximity to the 3/2 solenoid valve.12. The device of claim 11, further comprising: an air supply linecoupled to an input port of the 3/2 solenoid valve, the air supply lineincluding an air filter regulator to filter and regulate air supplied tothe input port; a second 3/2 solenoid valve with a first port coupledvia an air flow line to a working port of the first 3/2 solenoid valve,the second 3/2 solenoid valve being a universal type 3/2 solenoid valvewith an exhaust port; and a working flow line coupled between a secondport of the second 3/2 solenoid valve and a port of a single actingemergency isolation valve, the working flow line to providebidirectional air flow.
 13. The device of claim 11, wherein the flowcontrol valve is integrated with the vent port of the 3/2 solenoidvalve.
 14. The device of claim 11, wherein the electrical actuatorincludes a partial stroke testing limit switching circuit.
 15. Alocally-actuated partial stroke testing device for testing a doubleacting emergency isolation valve, comprising: a first solenoid valvewith an electrical actuator, a first vent port, a second vent port, afirst working port, and a second working port, the first and second ventports being operable to vent air from the first solenoid valve, and thefirst working port being coupled to a first flow control valve and thesecond working port being operable to regulate the air flow to a secondsolenoid valve coupled to the double acting emergency isolation valve;the first flow control valve operable to regulate the air flow to athird solenoid valve coupled to the double acting emergency isolationvalve; a second flow control valve coupled to the first vent port of thefirst solenoid valve, the second flow control valve being operable toregulate air flow; a valve position indicator to convey position of thedouble acting emergency isolation valve, the valve position indicatorbeing in visual proximity to the first solenoid valve.
 16. The device ofclaim 15, wherein the first flow control valve is integrated with thefirst working port of the first solenoid valve.
 17. The device of claim15, wherein the second flow control valve is integrated with the firstvent port of the first solenoid valve.
 18. The device of claim 15,further comprising a partial stroke testing limit switching circuit. 19.The device of claim 15, wherein the valve position indicator conveys apercentage of diameter of the double acting emergency isolation valveopen to fluid flow.
 20. The device of claim 19, wherein the valveposition indicator utilizes one or more of color, numerical,alphabetical, or graphical marks or combinations thereof to convey thepercentage of diameter of the double acting emergency isolation valveopen to fluid flow.